<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      // 把十进制数据转成几进制  num.toString(要转换的进制数)
      //   var num = 12;
      //   var res = num.toString(16);
      //   console.log(res);
      var num = "1111";
      var res = parseInt(num, 2);
      console.log(res);
    </script>
  </body>
</html>
